In this contribution, computationally efficient CELP structures are proposed for low-complexity speech coding below 6.4Kbits/s. We also report on a new approach for low bit rate speech coding using binary excitation pulses, which delivers the quality of the CELP codec without the excitation codebook storage, and with a very simple excitation determination procedure. Furthermore, we propose a switched-adaptive stochastic vector quantisation scheme for quantising the line spectrum frequencies using 22 bits without any perceivable spectral distortion.

Abstract

In this contribution, computationally efficient CELP structures are proposed for low-complexity speech coding below 6.4Kbits/s. We also report on a new approach for low bit rate speech coding using binary excitation pulses, which delivers the quality of the CELP codec without the excitation codebook storage, and with a very simple excitation determination procedure. Furthermore, we propose a switched-adaptive stochastic vector quantisation scheme for quantising the line spectrum frequencies using 22 bits without any perceivable spectral distortion.